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Pressure

ftH₂Otombar

Convert feet of water column (4 °C) (ftH₂O) to millibars (mbar).

Factor1 ftH₂O = 29.89067 mbar

Converter

ftH₂O

Accepts numbers or expressions, e.g. 150 + 14.7

Result
29.8907mbar

Rendered to 6 significant figures.

Formula

Formula
mbar = ftH₂O × 29.89067

Multiply any value in feet of water column (4 °C) by 29.89067 to obtain the value in millibars.

Worked example

Convert 1 ftH₂O to mbar.

  1. 01Start with 1 ftH₂O.
  2. 02Multiply by the conversion factor: 1 × 29.89067 = 29.8907 mbar.
Result1 ftH₂O = 29.8907 mbar

Conversion table

ftH₂Ombar
129.891
259.781
5149.45
10298.91
20597.81
501494.5
1002989.1
2005978.1
50014945
100029891

Reference values rounded to 5 significant figures for display.

FAQ

What is the conversion factor from ftH₂O to mbar?
1 ftH₂O equals 29.89067 mbar. To convert, multiply the value in feet of water column (4 °C) by 29.89067.
How do I convert 1 ftH₂O to mbar?
1 ftH₂O = 29.8907 mbar. For any value, multiply by 29.89067.
How do I convert mbar back to ftH₂O?
Divide by the same factor — or equivalently, multiply by 0.03345526. So 1 mbar = 0.0334553 ftH₂O.
When would I need to convert foot of water column (4 °C) to millibar?
Pressure conversions between ftH₂O and mbar are common when working with mixed-vendor instrumentation, when piping codes use different units to process datasheets, or when converting field readings into SI for hydraulic calculations.
Is the conversion exact?
The factor shown is precise to at least 7 significant figures. For most process-engineering work this is far better than instrument accuracy. For metrology or trade applications, refer to the relevant national standard (NIST, BIPM, ISO 80000).

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